In the electronics industry, devices such as relays are typically used to operate machinery and circuits. Such devices typically rely on energisation or switching on/off for operations.
Conventionally, for monitoring or control operations using a control relay, typically, the relay is specific to monitoring a certain overall parameter range of e.g. a power source, a voltage source, a current source etc. The parameter may be e.g. current, voltage, three-phase power etc. For example, a control relay may be provided for monitoring an overall current range of 0.15 A to 15 A. Practically, that control relay may be provided with different sub-ranges to be chosen by connection of the source to be monitored to different respective terminals. That is, the relay may have multiple input terminals corresponding to different monitoring ranges or sub-ranges. For example, the overall range may be broken up into sub-ranges such as 0.15 A to 1.5 A, 0.5 to 5 A and 1.5 A to 15 A. To monitor a current threshold of 6 A, a user typically needs to connect to two correct terminals (out of multiple terminals) for monitoring a sub-range of 1.5 A to 15 A.
Thus, one significant problem that may arise is that the user may connect the source to be monitored to incorrect terminals and the relay would then not function as desired. This may cause the user to interpret the relay as a malfunctioned product. Furthermore, a connection of a high current source to an incorrect terminal for monitoring a low current range may cause damage to the relay.
In addition, the user needs to know beforehand parameters of the source to be measured (e.g. the load current or the input voltage) in order to match according to product specifications of relays, to select the appropriate relay for monitoring and/or control purposes.
With multiple input terminals, the number for combinatorial permutations for selecting two input terminals (out of many terminals) can increase the complexity of operation of the relay. While user manuals are typically provided to tabulate the corresponding combination of two specific terminals with a particular source to be monitored, looking up such tables can typically be tedious and extremely time consuming.
Furthermore, as the process of looking up tables and identifying the correct input terminals for connection is currently manual in nature, a likelihood of human error still exists which may lead to product malfunction or damage. From a product supplier's perspective, this is highly undesirable as the number of product returns may increase and it may not be possible to differentiate damaged products which are caused by incorrect connection by users or actual defective products caused by e.g. manufacturing processes.
In addition, as the number of input terminals that can be present on a relay is ultimately limited by the usable surface area of the relay, a relay can only support a limited number of sub-ranges. Thus, in reality, different relays with different monitoring ranges are typically provided catering to different parameter thresholds. Therefore, there can be a large number of relays made available for a certain range thus leading to confusion for users. For example, there may be a relay for monitoring 0.003 A to 0.03 A of current, another relay for monitoring 0.01 A to 0.1 A of current, and yet another relay for monitoring sub-ranges 0.1 A to 1 A, 0.3 A to 1.5 A, 1 A to 5 A and 3 A to 15 A of current.
Hence, in view of the above, there exists a need for a relay and a corresponding method that seek to address or ameliorate at least one of the above problems.